The US aerospace and defence industry is urging House of Representatives lawmakers to reject a measure that would call a World War One-era massacre of Armenians by Turkish forces genocide, warning it could jeopardize US exports to Turkey.

The chief executives of Lockheed Martin Corp, Boeing Co, Raytheon Co, United Technologies Corp and Northrop Grumman Corp issued a rare joint letter, warning that passage of the measure by the House Foreign Affairs Committee could lead to “a rupture in U.S.-Turkey relations” and put American jobs at risk.

“Alienating a significant NATO ally and trading partner would have negative repercussions for US geopolitical interests and efforts to boost both exports and employments,” the CEOs warned in a Feb. 26 letter to the committee’s Democratic chairman, Representative Howard Berman.

They said US defence and aerospace exports to Turkey exceeded $7 billion in 2009 and were seen reaching a similar level in 2010, supporting tens of thousands of US jobs.

Industry executives are worried about Turkey’s continued participation in several big US weapons programmes, including the Lockheed F-35 fighter, a $1.2 billion deal with Boeing for 14 CH-47 Chinook helicopters, and Patriot missile sales.

Turkey is one of eight international partners working with the United States on development of the $300 billion F-35 fighter, a program that has already seen some erosion of overseas amid cost overruns and delays in critical testing.